Virtual machine instances are often configured to join one or more managed directories to enable users of these virtual machine instances to access certain data. For instance, an administrator of a virtual machine instance may use a set of credentials to authenticate himself/herself and perform one or more actions to join the virtual machine instance to a managed directory. This process can be performed manually, wherein the administrator uses his/her credentials through a graphical user interface or other application to join the virtual machine instance to a managed directory. However, the process of performing the domain join between the virtual machine instance and a managed directory can be labor intensive, adding expense and potential for error in the process. Additionally, this process may further expose the administrator's credentials as these credentials may be required to join the virtual machine instance to a managed directory within an alternative network.